Conclusion et recommandations

Les pesticides utilisés sont achetés dans la majorité des cas dans les marchés locaux (90%) sans garantie de conformité et de qualité. Les Pyréthrinoïdes sont les plus utilisés, alors que plusieurs auteurs ont souligné la résistance des ravageurs concernés (Bemisia tabaci et Helicoverpa armigera) à cette famille chimique. Cela va contribuer à intensifier les traitements et par conséquent à exposer encore les agriculteurs qui sont faiblement protégés, et les consommateurs (du fait du non- respect des DAR) aux risques chimiques. Les déchets de pesticides qui sont abandonnés dans la nature, et l’utilisation de doses souvent plus fortes que celles recommandées contribuent à polluer l’environnement.

Pour favoriser une gestion rationnelle des pesticides et limiter leurs impacts sur la santé humaine et sur l’environnement au Burkina Faso, plusieurs actions devraient être menées :

- En premier lieu, il faudrait conduire des actions de formation des producteurs et des vendeurs de pesticides pour améliorer leur connaissance des ennemis des cultures et des règles d’utilisation des pesticides ;

- En second lieu, il faudrait favoriser les contacts des producteurs avec les instituts de recherche et les services techniques du Ministère chargé de l’Agriculture de façon à ce qu’ils puissent réagir de façon appropriée à l’apparition de nouveaux ravageurs, ou de nouveaux risques ;

- Enfin il serait très utile de proposer des actions permettant une réduction de l’utilisation des pesticides en agriculture par la promotion et la vulgarisation des méthodes alternatives basées sur l’utilisation de la lutte intégrée, même si cette voie n’est pas facile à suivre comme le montre par exemple les difficultés d’application du plan Ecophyto en France (Guichard et al., 2017).

6.8. Remerciements

Cette étude a été réalisée avec le soutien financier de ARES-CDD (Projet PIC "Projet de Renforcement des Capacités de diagnostic et de gestion intégrée des Problèmes Phytosanitaires au Burkina Faso", UCL-ULg-IDR / UPB).

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Chapitre 7

Assessment of tomato (Solanum

lycopersicum L.) producers’ exposure level

to pesticides, in Kouka and Toussiana

(Burkina Faso)

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Assessment of tomato (Solanum lycopersicum L.)

producers’ exposure level to pesticides, in Kouka and

Toussiana (Burkina Faso)

D. Son1, 3_{*, F.K.B. Zerbo}1_{, S. Bonzi}1_{, A. Legreve}2_{, I. Somda}1_{, et B. Schiffers}3

1_{Université Nazi Boni (UNB), Institut du Développement Rural (IDR), Unité Santé des Plantes du}

Laboratoire Systèmes Naturels, Agrosystèmes et Ingénierie de l’Environnement (Sy.N.A.I.E), 01 BP1091 Bobo-Dioulasso (Burkina Faso)

2_{Université Catholique de Louvain (UCL), Faculté des Bioingénieurs,}

Earth and Life Institute (Belgium)

3_{Gembloux Agro-Bio Tech/ULg – Laboratoire de Phytopharmacie}

Passage des Déportés 2, 5030 Gembloux (Belgium) Ce chapitre est une version adaptée de l'article de recherche suivant :

Son D., Zerbo F.K.B., Bonzi S., Legreve A., Somda I., Schiffers B., 2018. Assessment of tomato (Solanum lycopersicum L.) producers’ exposure level to pesticides, in Kouka and Toussiana (Burkina Faso). (Publié dans Int. J. Environ. Res. Public Health 2018, 15, 204; doi: 10.3390/ijerph15020204).

7.1. Summary

To assess producers’ exposure level to pesticides in vegetable production in Burkina Faso, a study was carried out in 2016 and 2017 among 30 tomato producers in the municipalities of Kouka and Toussiana. Eighteen (18) commercial formulations were identified, with more than 50% of pesticides destined for cotton production. Eleven active substances have been identified and the most frequently used are _-cyhalothrin (35%), acetamiprid (22%) and profenofos (13%). The most commonly used chemical families are pyrethroids (28%) and organophosphates (18%). The study revealed a low level of training for producers, a high use of pesticides according to the Frequency Treatment Indicator, and a very low level of protection used by producers. The Health Risk Index shows that active substances such as methomyl, _-cyhalothrin and profenofos present very high risk to operators’ health. Based on the UK-POEM model, the predictive exposure levels obtained varied from 0.0105 mg/kg body weight/day to 1.7855 mg/kg body weight/day, which is several times higher than the Acceptable Operator Exposure Level. However, the study also shows that exposure can be greatly reduced if the required Personal Protective Equipment is worn. Producers’ awareness and training on integrated pest management are necessary to reduce the risks linked to the pesticides use in Burkina Faso.

Keywords: tomatoes, pesticides, risk assessment, UK-POEM, producers, Burkina Faso

Assessment of tomato producers’ exposure level to pesticides, in Kouka and Toussiana (Burkina Faso)

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7.2. Introduction

In Burkina Faso, tomato cultivation only takes second place to onions with a production of 289,572 tons on an area of 11,766.4 ha during the 2013-2014 vegetable season (MARHASA, 2014). However, this production is subject to many constraints, including pest pressure (Bemisia tabaci Gennadius, Helicoverpa armigera Hübner, Tuta absoluta Meyrick), which forces producers to intensify chemical treatments beyond suggested recommendations by overdosing or increasing the number of treatments (Konaté et al., 1995; Ouattara et al., 2017; Son et al., 2017a). Although plant protection products (PPP) enable satisfactory results in agricultural production, their use is risky to human health, the environment and non- target organisms (Alavanja et al., 2004; Tomenson and Matthews, 2009; Ouédraogo et al., 2014). This risk is higher because of the use in vegetable production of toxic and highly concentrated PPPs intended to combat pests in cotton without appropriate protective equipment (Schiffers and Mar, 2011; Son et al., 2017b). Surveys on phytosanitary practices in tomato production in Burkina Faso show that more than 70% of producers do not take adequate protective measures during PPP use (Son et al., 2017b). Several studies have shown that skin exposure remains the main risk allowing pesticide penetration into the human body (Macfarlane et al., 2013; Ouédraogo et al., 2014). This could explain the adverse effects experienced by producers (skin irritations, hot flushes, headaches, etc.) following pesticide application (Ouédraogo et al., 2009; Ahouangninou et al., 2011; Tarla et al., 2013). 72% of 316 producers, surveyed on their phytosanitary practices in tomato production in Burkina Faso, complained of acute poisoning during or after pesticide application (Son et al., 2017b). In addition to these acute effects, the chronic effects of pesticides on producers’ health, such as cancer, neurological diseases and reproductive disorders, have been highlighted by several authors (Kamel and Hoppin, 2004; Ouédraogo et al., 2014). On top of all this, a misuse of PPPs can also lead to consumer exposure (residues in food and water), environmental contamination (water and soil), emergence of resistant strains and auxiliary fauna destruction (Fernandes et al., 2010; Agbohessi et al., 2012).

Compared to cotton production, few studies have evaluated the potential exposure of Burkina Faso vegetables producers’ to pesticides (Ouédraogo et al., 2009; Ouédraogo et al., 2014). However, the significant development of vegetables gardening in Burkina Faso and the intensification of phytosanitary treatments, especially in tomato production, which have not been preceded by any impact study beforehand, justify this study considering that measuring the risk to operators is an obligation when registering PPPs (CILSS, 1999; EFSA, 2014).

It is in this context that this field study marked by close monitoring of some tomato producers surveyed in 2015-2016 (Son et al., 2017b), was carried out in 2016 and 2017, not only to further characterize their practices, assess the frequency and intensity of phytosanitary treatments, but also to assess the potential exposure of producers to these pesticides.

The importance of this paper after that on phytosanitary practices of tomato producers in Burkina Faso (Son et al., 2017b), is intended to once more draw the

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attention of producers and authorities to the risks associated in pesticides use and the necessity to apply the better phytosanitary practices.